Ghrelin, an acylated peptide consisting of 28 amino acids, is the endogenous ligand of the growth hormone secretagogue receptor (GHS-R). It is synthesized predominantly in the stomach but has been also identified in a variety of other organs. Alike, a wide range of central and peripheral endocrine and non-endocrine actions has been described, e. g. being a releasing factor of growth hormone, prolactin and ACTH, a modulator of cell proliferation and apoptosis, a regulator of sleep-wake regulation, and a orexigenic hormone. Aims of this study are: